Multiaperture core ring counter



W. K. ENGLISH MULTIAPERTURE CORE RING COUNTER Feb.- 20, 1968 Filed NOV.l2, 1963 United States Patent() 3,370,279 MULTIAPERTURE CORE RINGCOUNTER William K. English, Menlo Park, Calif., assignor to AMPIncorporated, Harrisburg, Pa. Filed Nov. 12, 1963, Ser. No. 322,760 9Claims. (Cl. 340-174) This invention relates to a multiaperture corering counter and more particularly to improvements therein.

A ring counter which uses multiaperture magnetic cores normallycomprises a shift register wherein one of the cores contains orrepresents a binary .1 with the rest of the cores representing a binary0. The count is advanced by shifting the register whereby the 1 isadvanced. Counting is usually done by supplying a trigger pulse to adriver circuit which then provides the appropriate pulses to shift theregister. If ring counters of this type are to be connected in series(as in the case of several stages of decade counters), or if ringcounters are to be used in connection with a magnetic system, each ringcounter must have its own driver. It would be advantageous if somemethodwere found to provide a single driver for a plurality of ringcounters where, however, when the driver is actuated, only the desiredring counter is advanced.

An object of this invention is to provide a ring counter structurewherein the advance pulses are applied continuously, but the count isonly enabled to advance in reply to an advancing signal.

Yet another object of the present invention is the provision of a ringcounter structure whereby a plurality of ring counters may be connectedto a single source of drive pulses, yet the ring counters may beindividually controlled in response to the application of individualadvance pulses.

Still another object of the present invention is the provision of anovel and useful arrangement for controlling the advance of a. magneticcore ring counter.

3,370,279 Patented Feb. 20, 1968 "ice counter can advance in response tothe application thereto of drive pulses.

The novel features that are considered characteristic of this inventionare set forth with particularit-y in the appended claims. The inventionitself both as to its organization and method of operation, as well asadditional Yet another object of the present invention is the proivision of an arrangement for controlling a plurality of ring counterswhich enables a saving in the cost of driver circuits required.

These and other objects of the present invention may be achieved in anarrangement for controlling the advance of a ring counter of the typewhich comprises two multiaperture ferrite magnetic cores per stage. Theoutput winding of the second core in eachstage is coupled `to drive thefirst core in that stage as well as the first core of the succeedingstage. Two control cores are provided at the input of the ring counter.One of these control cores has its output winding coupled to all thefirst cores in each stage of the ring counter in a manner so that whenthis control core is in its l state, it will inhibit the transfer fromthe one of the second cores in the one of the stages of the registerwhich is storing a binary 1 to the succeeding core in the next orsucceeding stage of the register, as a result of which the binary 1 istransferred to the first core in the register stage in which itpresently is stored. The second control core at the input of the ringcounter has its output winding coupled to all the first cores of eachstage of the ring counter in a manner so that when the second controlcore is in its l representative binary state, its output when drivenback to zero will block the transfer back within a stage of the binary lstate of the second core of that stage, resulting in the transfer to thesucceeding stage of the binary 1. Accordingly, as long as the first ofthe control cores at the input to the register are placed in their lstates, the counter will not advance despite the application thereto ofdrive pulses. When the second core at the input of the ring counter istransferred to its l state, then the ring objects and advantagesthereof, will best be understood from the following description whenread in connection with the accompanying drawings, in which:

FIGURE 1 is a schematic diagram of .an embodiment of the invention andFIGURE 2 illustrates schematically how the invention may be applied to aplurality of ring counters.

Reference is now made to FIGURE 1 wherein is shown a schematic diagramof an embodiment of this invention. As briefly previously described, thecircuit arrangement shown is one wherein the 1 which is in the ringcounter is shifted back and forth between the two magnetic cores withina single stage of the ring counter, in response to the drive or shiftpulses, and it is only when it is desired to count that the 1 ispermitted to advance to the next shift register stage.

The number of register stages in the ring counter Ais determined by thelargest number that it is desired for the ring counter to count. Thus,by way of example in FIGURE 1, an n stage ring counter is shown and foreach one of the n stages there are provided two multiaperture ferritemagnetic cores. The cores are respectively designated as even or oddcores in order to indicate that the cores are alternately driven. Instage 1 of the ring counter there is an odd core 11 and an even core 12.In stage 2 of the ring counter there is an odd core 13 and an even core14. Stage 3 of the ring counter contains an odd core 15 and an even core16, stage n of the ring counter contains an odd core n-I-10 and an evencore n-l-ll.

Each one of the odd cores in the register has a first and second inputaperture respectively, 11A, 11B, 13A, 13B, 15A, 15B, (n-l-10)A, and(n4-.10)B. Each one of the odd cores has an output aperture respectively11C, 13C, 15C, (n+10)C. All of the cores have main or central apertures,11M through (n-l-10)M.

Each one of the even cores has an input aperture respectively 12A, 14A,16A, (n-l-11)A. Each one of the even cores has an output aperturerespectively 12C, 14C, 16C, (n-i-11)C. All of the even cores also havecenter or main apertures, 12M through (n+11)M.

A first transfer winding respectively 21, 22, 23, Irl-20, respectivelycouples each one of the odd cores in a register stage to the even corein the same register stage. Thus the transfer winding 21 passes throughthe output aperture 11C of core 11 and thereafter passes through theinput aperture 12A of core 12 being wound on the legs of magneticmaterial adjacent these apertures in a well known manner to enable thetransfer of the remanent state of core 11 to core 12 upon a suitabledrive being applied to core 11. Similarly, transfer winding 22 couplescore 13 to core 14 by passing through the output aperture 13C of core 13then through the input aperture 14A of core 14. Transfer windings 23through n-l-20 similarly couple through the output aperture designatedwith the letter C in the respective odd cores to the input aperturesdesignated by the letter A in the respective even cores of therespective stages.

A second transfer winding respectively 31, 32, 33, 114-30, serves toapply the output from an even core to the input of an odd core withinthe same stage as the even core and also to an odd core in thesucceeding stage. Thus transfer winding 31 passes through the outputaperture 12C of core 12 and couples to cores 11 and 13 by passingthrough their input apertures respectively 11B, 13A. Transfer winding 32applies the output of core 14 to cores 13 and 15, passing through theoutput aperture 14C of core 14 then through the input aperture 15A ofcore 15 and then through the input aperture 13C of core 13 and back tothe output aperture of core 14. The transfer winding n+30, which is thetransfer winding in the last stage of the ring counter, applies theoutput from the last core n-l-11 to the core n+1() and also to the iirstcore 11 in the ring counter, passing through the output aperture (n+11)Cthen through the input aperture (n-l-)B, then through the input aperture11A and back to the output aperture (n+11)C of core 114-11. It should befurther noted that in the event an output indication is required fromthe ring counter when it attains a full count, the transfer winding114-30 and inhibit binding 74 may also couple to any suitable outputmanifestation device such as another core.

Every ring counter which is to be used with the ernbodiment of thisinvention will have the structures described thus far. In addition, eachregister may have three control cores respectively 41, 42, 43, fordetermining whether a ring counter is to advance its count or not, butactually, as will be described subsequently, it only requires two ofthese cores, 42, 43. The control core 41 iS associated with the oddcores of the ring counter. It has an input aperture 41A to which acurrent pulse is applied from an advance count input source 46, when itis desired to advance the ring counter in response to applied drivingpulses. Core 41 has a central or main aperture and in addition has anoutput aperture 41C. An advance odd current source 48 applies drivecurrent to a winding 50 which is coupled to all of the odd cores for thepurpose of driving them to their clear states when this winding isenergized. This winding, as is customary, passes through all the mainapertures of all the odd cores. Priming current is provided for all ofthe odd cores by means of a priming winding 52, driven from a prime oddcurrent source 54 when required, which priming winding passes throughall of the output or C apertures of all of the odd cores.

An advance even current source 56 applies current pulses to a drivewinding 58 for driving all of the even cores to their clear states. Thedrive winding 58 couples in well known fashion to all of the even coresby passing through their main apertures. As is well known, the advanceodd current source and the advance even current source operatealternatively to one another. A prime even current source 60 appliespriming current to a prime winding 62 for priming the output aperturesor C apertures of all of the odd cores.

It should be noted that in accordance with this invention only oneadvance odd current source, advance even current source, prime oddcurrent source, and prime even current source, is necessary for drivinga predetermined number of ring counters. Whether or not these ringcounters will advance their count in response to the current from thedrive sources is determined by the operation of the control cores 41,42, and 43. Since, as previously indicated, the ring counters onlyrequire one core to be driven at each operation of the advance currentsources, no great loading problem exists in driving several ringcounters from the one source of driving power.

Magnetic core 41 has two transfer windings 64, v66, one of which iscoupled to the input aperture 42A of core 42 with one sense, the otherof which is coupled to the input aperture 43A of core 43 with anopposite sense. When core 41 is driven from its one to its zerorepresentative state it drives core 42 to its one representative state.Core 43 is left in its zero representative state since transfer winding66 is also coupled to a small core 70. It is also to be noted that theadvance odd current winding 50 is coupled to core 70 with one sense andthe advance even current winding 58 is coupled to core 70 with anopposite sense. The prime odd current winding 52 passes through theoutput aperture 41C of core 41 to prime the magnetic materialsurrounding this output aperture should core 41 have been driven to itsl representative state in response to a current pulse from the holdcount input source.

The prime even current source winding 62 is coupled to cores 42 and 43by passing through their output apertures respectively 42C, 43C, inaddition to passing through the C apertures of the other even cores ofthe ring counter. Core 42 has an inhibit winding 72 which is inductivelycoupled to the core material, passing through the output aperture 42Cand thereafter is coupled to all of the odd cores of the ring counterpassing through their B input apertures. Core 43 similarly has aninhibit winding 74 which is coupled to the core by passing through itsoutput aperture 43C and thereafter is coupled to the odd cores of thering counter passing through their A input apertures successively.

In operation of the embodiment of the invention, the drive currentsources operate in the same manner whether for one or for a plurality ofring counters, as they have done heretofore. The advance odd currentsource applies a suiiicient current to the odd core drive winding S0 todrive the one of the odd cores which is coupled thereto and which is inthe remanence state wherein it represents a one, to the remanence statewhere it represents a zero. This followed by the prime even currentsource 60 applying a priming current to the prime winding 62 whereby theone of the even cores which represents a binary one by its state ofremanence is primed. Then the advance event current source is energizedwhereby the even core drive winding 58 drives the core coupled theretowhich is in its one representative remanence state to its zerorepresentative remanence state, thus transferring ferring the one to oneof the odd cores. Then the prime odd current source 54 is energized toapply a current to the prime odd core winding 52 whereby the one oftheodd cores which is in its one representative state is primed. However,despites the norma operation of the drive sources for the ring counter,as will be explained subsequently herein, the ring counter does notadvance its count beyond the stage in which the count reposes, solely inresponse to the drive current pulses.

Assume now that core 13 is in its one representative state of remanence,and that it is not desired to advance the count of the counter. In thatinstance, no advance count input signal is applied to core 41. The primeodd current source 54 applies priming current to the prime winding 52,whereby core 13 is primed. The advance Wmding 50 is next driven by acurrent pulse from the advance odd current source 48 in response towhich core 13 is driven to its clear state and its state of remanence istransferred over transfer winding 22 to core 14. Core 70 is driven toits one state each time the advance even current source 56 energizes theclear winding 58. When the advance odd core winding 50 receives acurrent pulse, it clears core 70 whereby sul'licient current flows intrans- -fer winding 66 to drive core 43 to its one state. Core 41 1s notchanged since it is in its zero state. The prime even current source 60next energizes the winding 62 with a pruning current pulse in. responseto which core 43 and core 14 are driven to their prime states. Next inresponse to an output current from the advance even current source 56,the drive winding 58 transfers cores 43 and 14 to their clear states. Avoltage is induced in winding 32 from core 14 being driven with aresultant current flow which is applied to both cores 13 and 15 to drivethem toward their set states of remanence. However, in view of an outputon inhibit winding 74, which is coupled to input aperture 15A, and whichoutput opposes the magnetomotive force being applied from winding 32,core 15 remains unaffected and the magnetomotive force which isgenerated due to the current ilow in winding 32 is all applied to core13 to drive it to its set state of magnetic remanence. As a result, thecount of the ring counter was not advanced but remains within the secondstage of the register.

From the foregoing, it will be seen that with no advance count signalapplied to core 41, core 43 is driven to its one representative state sothat its output may oppose the output from the even core which otherwisewould transfer the count into the succeeding stage of the counter.v

Should it be desired to permit the ring counter to advance its count,then core 41 is driven to its binary one state of magnetic remanence byan output from the advance count input source 46. Energization of theprime odd current source 54 applies priming currents to winding 52whereby cores 41 and 13 are primed. A current pulse is applied to theadvance odd winding 50 from the advance odd current source 48 wherebycores 41 and 13 are driven to their clear state. In response to this,core 14 is driven to its one representative state of magnetic remanence.Core 42 is driven to its one representative state of magnetic remanenceand core 43 is left in a zero representative state of magneticremanence, even though core 70 was driven to its clear state from itsone state by the advance odd winding. This occurs because any outputcurrent flowing in winding 66 as a result of core 41 being driven iscancelled by current owing as a result of core 70 being driven. Thetransfer winding opposite coupling sense on core 70 and core 41 insuresthis.

The prime even current source 6G then applies a priming current towinding 62 whereby cores 42 and 14 are driven to their prime states. Theadvance even current source 56 next applies a current pulse to winding58 whereby cores 42 and 14 are driven to their clear states of magneticremanence. In response to this drive, a cur rent is induced in theinhibit winding 72 which opposes the effects of the current in thetransfer Winding 32 at aperture 13B. As a result, the magnetomotiveforce caused -by the current in winding 32 is applied to drive core 15to its one representative state of magnetic remanence. This then is anincrease or an advance of the count of the ring counter to thesucceeding stage. Each time it is desired to advance the count of thering counter, it is required to apply an advance count pulse to the core41. Otherwise, the one in a stage of the ring counter remains withinthat stage.

From the foregoing description, it will be seen that a ring counter willadavnce its count only in response to a control pulse applied to thecontrol core 41. Core 41 also can act to receive advance count pulsesfrom other sources such as another ring counter. The control of the ringcounter is efectuated by means of an inhibit technique which permitshandling a considerable number of cores. The reason for this is thatwhen either core 42 or 43 is transmitting a one, current in the inhibitwinding from that core does not actually switch any iiuX but serves onlyto inhibit switching in the receiver core to which it is linked. Currentin the inhibit loop from these cores is then essentially independent ofthe number of receiver cores linked, and the single control core couldtheoretically control a large number of receiver cores. Practicallimitations on this can be considered as the wire length and a smallzero ux switched around the input apertures of cores not receiving a oneFIGURE 2 is a schematic diagram illustrating how the embodiment of theinvention is employed for controlling a multiplicity of ring counters. Asingle set of drive current sources 80 (Advance Even, Advance Odd, PrimeOdd, Prime Even) is required. These are coupled to all of the counters,respectively S2, 84, 86, in the manner shown in FIGURE l. The countercircuits are wired in the manner shown in FIGURE 1. A set of Vcontrolcores, respectively 88, 90, 92, each wired as in FIGURE l, are providedfor each counter. A control core control, 94, 96, 98 is provided tocontrol the control cores, respectively 88, 90, 92. The control corecontrol represents the advance count input source 46.

Each counter shown in FIGURE 2 operates identically as has beendescribed for the counter shown in FIGURE 1. Although the -drive currentsources continuously apply drive pulses to all of the counters, theywill individually only advance or remain stationary under control of thecontrol cores associated with each, in response to the individualcontrol core control.

There has accordingly been described and shown herein a novel, usefuland unique arrangement whereby a plurality of ring counters may beindividually controlled while having a single source of driving currentfor these ring counters.

I claim:

1. Apparatus for operating a plurality of ring counters individuallywhile employing a single set of drive current sources for said ringcounter comprising for each ring counter, a plurality of registerstages, each stage including two magnetic cores each of which has a onerepresentative state of magnetic remanence and a zero representativestate of magnetic remanence, one core in each stage being designated asan odd core and the other core in each stage being designated as an evencore, in each stage a transfer winding means coupling said odd core tosaid even core for transferring the state of remanence of said odd coreto said even core, in each stage a second transfer winding meanscoupling each even core to the odd core in its stage and to the odd corein the succeeding stage for transferring the state of remanence of saideven core to said odd core, first inhibit means actuatable forpreventing the transfer of the state of magnetic remanence by saidsecond transfer winding means to a succeeding stage odd core, and secondinhibit means for inhibiting the transfer by said secondtransfer windingmeans to an odd core in the same register stage.

2. A system for controlling the advance of a counter of the typecomprising a plurality of stages, each stage having a rst and a secondmagnetic core, each of the said magnetic cores having a zerorepresentative stable state of magnetic remanence and a onerepresentative stable state of magnetic remanence, transfer windingmeans coupling each said second core to the first core in the same stageas said second core and to the first core in the stage succeeding thestage of said second core for transferring one of said rst cores to aone representative state of magnetic remanence in response to one ofsaid second cores being transferred from a one representative state ofmagnetic remanence to a zero representative state of magnetic remanence,first inhibit means actuatable to inhibit each rst core in the stagesucceeding each second core against being transferred to its onerepresentative state of magnetic remanence in response to the secondcore in a preceding stage being driven from its one to its zero state ofmagnetic remanence, and second inhibit means actuatable for preventing arst core from being driven to its one representative state of magneticremanence in response to a second core in the same stage being drivenfrom its one representative state of magnetic remanence to its zerorepresentative state of magnetic remanence.

3. A system as recited in claim 2, wherein said rst and second inhibitmeans each comprises a magnetic core having a zero representative stablestate of magnetic remanence and a one representative stable state ofmagnetic remanence, and an inhibit winding coupled to said magneticcore, said inhibit winding of said iirst inhibit means being coupled toall of said rst cores, in the same stage as a second core, said inhibitwinding of said second inhibit means being coupled to all of said iirstcores in the stages succeeding those of the second cores, means fordriving said rst inhibit means core to its one representative state whenit is desired to permit said counter to advance its count, means fordriving said second inhibit means magnetic core to its onerepresentative state when it is desired to prevent said counter fromadvancing its count, and means for applying a drive to said cores ofsaid first and second inhibit means to drive the one of them in its onestate to its zero state simultaneously with the application of a driveto all said second cores to transfer the one of them in its one state toits zero state.

4. In a ring counter of the type wherein each stage of said ring countercomprises an odd and an even magnetic core each of which has a onerepresentative state of magnetic remanence and a zero representativestate of magnetic remanence, and the count in said counter is advancedby transferring the one representative state of magnetic remanencesuccessively from an odd core to an even core in one stage andthereafter, to an odd core in the succeeding stage of said counter, theimprovement comprising means for coupling each even core in a stage ofsaid ring counter to the odd core in the same stage and to the odd corein the succeeding stage for applying drives to said odd cores to theirone representative states of magnetic remanence when said even core isdriven to its zero from the one representative state of magneticremanence, first means for inhibiting the drive to each odd core in thesame stage as an even core being transferred to its zero from its onerepresentative state when it is desired to advance the count of saidcounter, second means for inhibiting the drive to each odd core in thestage succeeding the stage of an even core lbeing driven from its one toits zero representative `state when it is desired to prevent saidcounter from advancing its count, and means for selectively actuatingone of said first and second means for inhibiting.

5. A counter control system comprising a counter having a plurality ofstages, each stage including an odd and an even multiaperture magneticcore, each magnetic core having a one representative state of magneticremanence, each odd multiaperture magnetic core including a first andsecond input aperture and an output aperture, each even multiaperturemagnetic core including an input aperture and an output aperture, afirst transfer winding for each stage of said register, said firsttransfer Winding coupling each odd core through its output aperture toeach even core through its input aperture, a second transfer winding foreach stage of `said register, said second transfer Winding coupling eacheven core in a stage of said register through its output aperture toeach odd core. in the same stage of said register through its secondinput aperture and coupling said even core to the odd core in thesucceeding stage of said register through its first input aperture,first inhibit Winding means actuatable for preventing said counter fromadvancing its count, said first inhibit winding means 'being inductivelycoupled to all said odd cores through their first input apertures,second inhibit winding means selectively actuatable for enabling saidcounter to advance its count, said second inhibit winding means beingcoupled to all the odd cores of said ycounter through their second inputapertures, and means for selectively exciting one of said first and saidsecond inhibit winding means simultaneously With a. drive being appliedto one of said even cores for inducing a voltage in the second transferWinding coupled to said one of said even cores, whereby the count ofsaid counter is maintained or advanced in accordance with the one ofsaid first and second inhibit windings which Was excited.

6. Apparatus as recited in claim wherein said means for selectivelyexciting one of said first and said second inhibit winding meanscomprises a first and second multiaperture magnetic core, each said corehaving a first stable stae of magnetic remanence and a second stablestate of magnetic remanence and being drivable therebetween, means forcoupling said first inhibit winding means to said first magnetic core tobe excited in response to said first magnetic core being driven from itsfirst to its second stable state of magnetic remanence, and means for:coupling said second inhiibt Winding means to said second magnetic corefor being excited in response to said second magnetic core being drivenfrom its first to its second state of magnetic remanence, said means fordriving said even cores also being coupled to said first and secondmagnetic cores for driving said first and second magnetic cores fromtheir first to their second stable states of magnetic remanencesimultaneously with a drive being applied to all of said even magneticcores.

7. Apparatus as recited in claim 6, wherein said means for selectivelyexciting one of said first and second inhibit windings includes an inputmultiaperture magnetic core having first and second stable states ofmagnetic remanence and being drivable therebetween, said input corehaving a first output Winding coupling said input core to said firstmultiaperture core for driving said first multiaperture core from itssecond to its first state of magnetic remanence when said input core isdriven from its first to its second state of remanence, a second outputwinding, and a bucking magnetic core having a first and a second stateof magnetic remanence, said second output winding coupling said inputcore to said second multiaperture core for driving said firstmultiaperture core from its first t0 its second state of magneticremanence 4when said input core is driven from its first to its secondstate of remanence, said bucking magnetic core being coupled to saidsecond output winding for driving said second multiaperture core fromits second to its first state of remanence when said bucking core isdriven from its first to its second state of magnetic remanence.

8. Apparatus for controlling magnetic core counters comprising a counterhaving a plurality of stages, each stage including an even and an oddmultiaperture magnetic core, each multiaperture magnetic core having aone representative state of magnetic remanence and a zero representativestate of magnetic remanence, each odd multiaperture core having a firstand a second input aperture and an output aperture, each evenmultiaperture core having an input aperture and an output aperture, foreach counter stage, there being provided a first transfer winding fortransferring the state of remanence of an odd multiaperture Core to aneven multiaperture core, said first transfer winding being inductivelycoupled to said odd multiaperture core through its output aperture andto said even multiaperture core through its input aperture, for eachstage of said counter there being a second transfer Winding inductivelycoupling an even multiaperture core by passing through its outputaperture to an odd multiaperture core in the same stage as said evenmultiaperture core by passing through its second input aperture and tothe odd multiaperture magnetic core in the succeeding stage of saidcounter by passing through its first input aperture, first inhibitwinding means for providing when energized magnetomotive forces tooppose those from said second transfer winding, said first inhibitWinding means lbeing coupled to all of odd cores in said counter throughtheir second input apertures, second inhibit winding means for providingwhen energized magnetomotive forces to oppose those of said secondtransfer winding, said second inhibit winding means being coupled to allof the odd cores in said counter through their first input apertures, afirst and a second multiaperture core each having a first and secondstate of stable magnetic remanence, said first multiaperture core beinginductively coupled to said first inhibit winding means for inducing avoltage therein when said first multiaperture core is driven from itsfirst to its second stable state of magnetic remanence, said secondinhibit winding means being coupled to said second multiaperturemagnetic core for having a voltage induced therein when said secondmultiaperture magnetic core is driven from its first to its second stateof stable magnetic remanence, means for applying a drive to all of saidodd magnetic cores for driving them from their one to their zero statesof stable magnetic remanence, means for driving one of said first andsecond magnetic cores to its first state of stable magnetic remanence todetermine whether said counter will advance its count or will notadvance its count on the next drive applied to said even magnetic cores,and means for applying a drive to said first and second magnetic coresand to all of said even magnetic cores for driving the one of said rstand second magnetic cores from its first to its second state of stablemagnetic remanence and the one of said even magnetic cores from its oneto its zero representative state of magnetic remanence, Whereby one ofsaid odd magnetic cores either in the same stage as said even magneticcore being driven or in the succeeding stage will be driven to its onerepresentative state of magnetic remanence as determined by the one ofsaid rst and second cores which was driven from its rst to its secondstate of stable magnetic remanence.

9. Apparatus as recited in claim 8 wherein said means for driving one ofsaid rst and second magnetic cores to its first state of magneticremanence includes a third magnetic core having a irst and second stablestate of magnetic remanence, a first output winding coupling said thirdmagnetic core to said irst magnetic core for driving said rst magneticcore to its rst state of remanence in response to said third core beingdriven from the rst to its second state of remanence, a second outputwinding coupling said third core to said second core for driving saidsecond core to its second state of magnetic remanence in response tosaid third core being driven from its first to its second state ofremanence, and a bucking magnetic core having a rst and a second stateof magnetic remanence and being coupled to said second output windingwith a sense for driving said second core to its first state ofremanence when said ybucking core is driven from its rst to its secondstate of remanence, said third magnetic core and said bucking core beingcoupled to said means for applying a drive to all said odd magneticcores to be respectively driven responsive thereto to their second andtheir first states of remanence, said second and third magnetic coresand said bucking core being coupled to said means for applying a driveto said even magnetic cores for being driven responsive thereto to theirsecond states of magnetic remanence.

References Cited UNITED STATES PATENTS 5/1962 Bennion 340--174 3/1964Bennion 340-174

1. APPARATUS FOR OPERATING A PLURALITY OF RING COUNTERS INDIVIDUALLYWHILE EMPLOYING A SINGLE SET OF DRIVE CURRENT SOURCES FOR SAID RINGCOUNTER COMPRISING FOR EACH RING COUNTER, A PLURALITY OF REGISTERSTAGES, EACH STAGE INCLUDING TWO MAGNETIC CORES EACH OF WHICH HAS A ONEREPRESENTATIVE STATE OF MAGNETIC REMANENCE AND A ZERO REPRESENTATIVESTATE OF MAGNETIC REMANENCE, ONE CORE IN EACH STAGE BEING DESIGNATED ASAN ODD CORE AND THE OTHER CORE IN EACH STAGE BEING DESIGNATED AS AN EVENCORE, IN EACH STAGE A TRANSFER WINDING MEANS COUPLING SAID ODD CORE TOSAID EVEN CORE FOR TRANSFERRING THE STATE OF REMANENCE OF SAID ODD CORETO SAID EVEN CORE, IN EACH STAGE A SECOND TRANSFER WINDING MEANSCOUPLING EACH EVEN CORE TO THE ODD CORE IN ITS STAGE AND TO THE ODD COREIN THE SUCCEEDING STAGE FOR TRANSFERRING THE STATE OF REMANENCE OF SAIDEVEN CORE TO SAID ODD CORE, FIRST INHIBIT MEANS ACTUATABLE FORPREVENTING THE TRANSFER OF THE STATE OF MAGNETIC REMANENCE BY SAIDSECOND TRANSFER WINDING MEANS TO A SUCCEEDING STAGE ODD CORE, AND SECONDINHIBIT MEANS FOR INHIBITING THE TRANSFER BY SAID SECOND TRANSFERWINDING MEANS TO AN ODD CORE IN THE SAME REGISTER STAGE.